Electric flatiron



Feb. 3. 1925. 11,525,388

W. T. HOOFNAGLE ELECTRIC FLATRON Filed Oct. 2l, 1922 2 Sheets-Sheet l Feb. 3. 1925. 1,525,388

A W. T. HOOFNAGLE ELECTRIC FLATIRON 2 Sheets-Sheet 2 Filed Oct. 2l, 1922 Patented F eb. 3, 1925. I.

UNITED STATES PATENT OFFICE.

WILLIAM T. HOOFNAGLE, F GLEN RIDGE, NEWIJERSEY, ASSIGNOR T0 THE COMFO ELECTRIC IRON COMPANY,r OF GLEN RIDGE, NEW JERSEY, .A CORPORATION OF NEW JERSEY.

ELECTRIC vFLA'IJIRON'.

To all ri/omit may concern.:

Be it known that I, WILLIAM T. Hoor- NAGLE, a citizen of the United States, residing at Glen Ridge, in the county of Essex and State of New Jersey, have invented certain. new and useful Improvements in Electric Flatirons, of which the following is a specication.

. protected from the heat of the iron.

In carrying out the invention, I provide a top or cover for the iron which is made entirely of heat insulating material and the handle is secured to this top. The top con- I ines the heat to the base, increasing the eiiiciency of the iron and protecting the operators hand from the heat of the iron. Within an opening in the top is arranged a fuse plug having clamping members at its lower end adapted to retain a fuse within the space above the base which is enclosed by the top. This fuse forms part of the electric circuit through the heatin element and when the iron becomes excesslvely hot, the fuse melts and interrupts the circuit through the heating element. Within the plug and in series with the fuse and heating element is a filament which is visible through the top of the plug and remains luminous while the current is on. By observing this tilament the operator can tell at a glance whether the current is on or off and this lessens the danger of the current being left on when the iron is not in use. If the operator fails to note that the current is turned on when the iron is set aside and does not disconnect the iron from the supply circuit, the overheating of the iron will cause the fuse to melt and the circuit through the heating element will thereby bc interrupted. The fuse plug is provided with clamping members adapted to grip the fuse when the plug is screwed into a socket in the cover and is s o constructed that no current can flow through the heating element of the iron unless a fuse is placed between the clamping members. The invention also includes certain structural features of the plug and associated parts which will be hereinafter pointed out.

In the accompanying drawing, f

Fig. l is a longitudinal verticali section through the iron on the line 1--1 of Fig/2;

F ig. 2 is a top plan view of the iron, the electrical circuits being shown in' dotted lines;

Fig. 3 is a vertical cross section through the iron on the line 3-3 of Fig. 2;

Fig. 4 is a top plan view of the body portion of the fuse plug;

Fig. 5 is a similar view of the insulating ring which forms an extension of the socket in the cover;

Fig. 6 is an edge view of the same;

Fig. 7 is a top plan view of the movable fuse-clamping member;

Fig. 8 is a plan view of one of the fuses bent into shape for use; and,

Fig. 9 is a, top plan view of the connecting plate with the shell of the socket attached.

Referring to the drawing, a represents the base of the iron, which is of the usual form, having a heating element l, indicated iu dotted lines, embedded in electrical insulating material 2. The top or cover b of the iron is of molded heat insulating material, preferably an asbestos composition, relatively thick in its central portion and having a flange b at its edge which engages the perimeter of the base and spaces the central port-ion of the body away from the base. The top has embedded therein interngall threaded sockets 3 and 4:, adapted to receive machine screws 3a and 41a, respectively,

which secure the handle to the top. is

shown, the handle comprises a hand piece or grip 5, to the ends of which are attached t the lends of a metal strip 6, bent into the form of a bail 'and having a straight central portion 6E through which the screws extend into the threaded bushings or sockets in the top. rihe top, being composed entirely of 1 a relatively thick body of heat insulating material, prevents upward conduction an radiation of the heat from the base, and as the metal bail or strap of the handle is secured to this insulating material the heat cannot be conducted from the base through the bail to the core of the grip. Hence, the grip will remain relatively cool to the touch and the top will protect the operators hand against radiant heat from the base.

llO

The top is secured to the body by a centrally located screw 7 which extends through a downwardly extending boss 8 upon the body and into the base, the head of the screw being counte-rsunk in the top, as shown in dotted lines in Figs 1 and 2. For positioning the top with respect to the base, the top is provided with downward projections 9 and .10 at the front and rear ends thereof, respectively, which projections engage the outer wall of therecess 1l in the base, wherein the heating element is located. n v

At one side of the handle the top is formed with a depression .12which constitutes a pocket Y. for holding a supply of fuses 13, and to retain the.fuses in place the pocket is provided with' a cover plate 147- 'removably secured to the top by machine screws, one of which is shownatl. i

A circular, opening 16 extends through .the bodvof thetop at the side opposite thev aforesaid' pocket, and within this opening is arranged a threadedmetal Ycontact shell 17, adapted to receive a similar contact-shell 18 on the outer side lof a fuse plug c. The body 19 of the plug is made of suitable insulating 'materiah such as orcelain, and is hollow, and is provided with a transparentv cover 20, as usual, the latterv being held 1nv place by a sheetmetal". ring 21, flanged about the rim orv bead 22 of the body. The ring 21 is provided withv alined'v notches 23 so that the plugv can be turned with the blade of a knife, if it sticks and cannot be .turned by the ngers of the operator. The

baseof the body portion of the nlug has ank opening extendinglcentrally through it, the lower (part 24 of 'the` opening being cylindrical an lthe upper part 24a being squared or angular in cross section, and on the bottom` of the body portion isV anannular projetstion 25l which forms a stop for a purpose` hereinafter described. V'O11 the` bottom of thef body portion and surrounding said stop is a flat metal contact lring v26 whichV is elec- 'disk 32, having a central shank orxstem 32 body.

tricallyv connected to af metal ring 27 i in the bottom" of the cavity in thesocket by screws 28 which clampv both' rings to thev A filament support 29 is lconnected to the ring 27 anda.' similar support. 30 is connectedto the threaded 4 contact shell 18 of the plug, and ag'filament 31'ofnon-oxidizable metal, such as platinum, is connected v between n these supports beneath the transparent cover orwindow 20.' Thus. the plate 26 selectricallyconnected. through the filament to the sidecontact shell-'of the plug.

. The ring' 26 constitutes one member of a fusev clamp,l the :other member comprising a which extends upwardlythrough the cylindrical opening 24 in the body of the plug and into the squared openingA 24, and has securedto its upper end, a squared head 32 which-prevents the shank and disk from turning with respect to the body of the plug. The shank is movable lengthwise in the opening so that a fuse wire. indicated at 33, may be clamped between the disk and the ring 26. The disk has in its upper side an annular ychannel 32, for receiving the fuse metal if the fuse melts. The fuse electrically connects the clamping members 26 and 32 when the fuseis gripped between them. If the fuse is removed, t-he clamping` members cannot come in Contact with one another because of the downward projection 25 on the insulated bodv which forms a stop to prevent such engagement. The cur` rent which flows through the heating element of the iron and the filament also flows throughthe cla-uncinor members and the fuse. as hereinafter explained. It will be evident. therefore. that the iron cannot be used unless the plus is fused, vas the stopv 25 will prevent theclamping members 'from engaging one another and the electrical circuitl will be open between said members. The distance which the stop 25 projects below the clamping ring-26is less than the diameter y `the insulating material 2 in which thel lwa.

ing element is embedded. Y This contact piece, as shown. is preferably in the form of `a pan having its central portion pressed upwardlyv as shown at 34, `and adapted to be engaged-by the central portion of the disk 32 andhaving its marginal portion 34a fiaring outwardly and upwardly in'order that it may be. centered beneath the plug and kept in position by a ring of insulating material 35 which is alined with the'opening.r 16 in the top .ofl the iron. .The contact piece al has secured to its edge ametal strip 34b which connects the contact piece with aterminal 36, which is embedded in the insulating material 2.l 4One end of the heating wire or element' '1 -is connected to said .terminah as indicated in dotted linesv in Fig. 2.

`A`plate"17a, to which the Contact shell 17 is welded, is .secured to the underside of the top b by a bolt 37 which extends through anA opening inthe top and is provided with a strip 34" Ato the binding post 36 and set in itsA approximate position on the insulating material 2. When the top is placed upon the iron, the tubular member 35 is placed over the contact -piece 34 and when the top is adjusted to its position on the base, the contact piece 34 will be centered at the bottom of the opening 16 in which the fuse plug fits.

The usual terminals by which the iron is connected to the electric supply circuit, through flexible conductors, areindicated at 40 and 41. These extend through the top or cover b, as shown and are secured directly thereto, the cover forming an insulating v support for the terminals. The terminal 40 is connected by a flexible conductor 42 to a binding post 43, which is embedded in the insulating material 2 in the base of the iron, and from this terminal the heating wire or coil 1 extends toward the front of the iron and then back to the terminal 36, as shown in dotted lines in Fig. 2. This circuit then proceeds through connection 34b to the stationary contact d, thence through clamping member 32 to the fuse 33 and to the clamping ring26, thence through screws 28 to the ring 27 in the plug, thence through filament support 29, filament 31 and filament support 30 to the contact shell 18 on the plug, thence through the outer shell 17 and its supporting plate 17 to a metal strip 44 which connects said plate to the supply terminal 41. It will be evident from this description that when the iron is connected to the supply circuit, the current will fiow through the heating element, the fuse and the filament in series.

The fuses in the storage pocket are straight; but when a fuse is to be used it is bent into a more or less semi-circular form, as shown in Fig. 8, and placed between the clamping members of the plug.

It will be understood from the foregoing that when the iron is to be used, the plug will be inserted in the socket, with a fuse between the clamping members. As the plug is turned in the socket, the' clamping member 32 engages the stationary contact d and the further turning of the plug causes the clamping members to grip the fuse. lf, now, the current is turned on, the heating element will cause the base of the iron to become heated and the filament 31 will become luminous and serve as a signal to the operator that the current is flowing through the heating element. In the active use ot the iron, the heat inthe base is dissipated by the contact of the base with the fabrics 'which are being ironed; but it' the operator should allow the iron to stand for a time without use, the iron would become over-heated. This excessive heat in the cavity above the base wherein the fuse Yis located would cause the fuse to melt when a pre-determined temperature is reached. If the fuse melts by reason of this excessive cuit through the heating element by electrically dis-connecting the. clamping members. The fuses are proportioned so that they will melt before the base of the iron reaches a high enough temperature to causedamage to wood or fabrics.

The main purpose of the filament is to enable the operator to see whether the current is on or ofi' when the iron is set aside. If' the filament glows when the iron is set aside, of course, the operator will be reminded to disconnect the iron from the supply circuit. If the operator fails to do this, then the fuse will melt before the iron reaches a dangerous heat, as above dcscribed.

It will be evident that the operator can not use the iron without having it fused since the circuit through the heating element cannot be completed through the clamping members if the fuse is absent, by reason of the insulating projection 25 on the socket which prevents said members from contacting in the absence of the fuse.

The insulating ring 35 serves as a guard to prevent molten fuse metal from becoming scattered over the heating element.

What I claim is:

1. In an electric fiat iron, a base having a heating element and a contact member, a cover having a socket provided with an internal contact, supply terminals on the cover, one of which is connected through the heating element to the contact member of the base and the other of which is connected to said contact in the socket, and a fusev plug having a contact adapted to engage the contact in the socket and hav ing a metal clamp at its base adapted to grip a fuse, one member of said clamp being adapted to bear against the contact member on the base of the iron when the plug is in the socket.

2. ln an electric fiat iron, a base having a heating element land a contact member, acover having a socket provided with an internal Contact and a fuse plug having a side contact adapted to engage the contact in the socket and having a metal clamp at its base adapted to grip a fuse, said clamp comprising a member fixed to the end of the plug and a member movable with respect to said fixed member and adapted to bear against the contact member on the base of the iron when the plug is in the socket.

3. The combination with an electric flat iron having a base provided with a heatin element and a contact connected thereto an having a cover provided with a socket, of a fuse plug adapted to fit into said socket, said plug comprising a body or insulating material having anl opening in its base, a,

metal disk having a stem movable longitudinally in said opening, and a metal ring said fplug 'comprising a body of insulatingr material having an opening in ,its base, a

' metal disk having a stem'movable longitudinally in said opening, said disk having'an annular channel in the side next the plug,

and a metal ring 'on the body opposed to said disk, saidv disk adapted to engage the contact on the basel of the ironl when the plug is-in the socket.Y f e 5. The combination `With anelectricl at iron having av baseprovided with a heating elementl and a contact connected" thereto andl having a cover provided` v vithA a socket,'-of a fuse plug adapted to .itinto'said` socket,

. said plug comprising a body .ofinsulating material having-metal clamping members at W said clamping members,'one'of said clam ing members being adapted to" engage t e itsv base, said body havmg a projection adapted` .to prevent the o o-'engagement of contact on thev base of the iron when the plug is in the socket.

'6. In van electric iatviron, a base having a heating element embedded in insulating material and a circular contact member connected to said element and resting on said material, a cover having a socket and a ring of insulating material registering with .said socket and` surrounding said contact' member, and a.;plug adapted to fit in said socketand having a fuse clamp at its base adapted to engage said contact member.

7 .'*Inr an electric flat iron, a base having a heating element and a cover composed of heat insulating material extending over the base and enclosing the heating element,

a handle securedv to said cover, and a fuse plug extending through thev cover and engaging a. metal'partion the base.

8. an electricflat iron, a base having a heating element, -a cover-composed of heat vvinsulating material Jextendin lover the base and enclosing the Aheating e ement, supply circuit ,terminals-secured" directly to said i cover,"and la fuse"plug extending through Vthe cover and-engaging a metal part on'the base .Y

. In testimony signatureh f WILLIAM fr; HooFNAGLE.

whereof I hereunto aiiix my 

